Alkamin ester.



UNITED STATES PATENT OFFICE.

FRlEDRICH 'STOLZ AND GEORG KORNDORFER, orHocHsT-oN-THE-MMN, GERMANY, 'Assrcnons TO FARBWERKE VORM. MEISTER Looms & BRUNING, or HOOHST-ON-THE-MAIN, GERMANY, A CORPORATION or GERMANY.

ALKAIVIIN ESTER.

Specificationof Letters Patent.

Patented Aug. 7, 1906.

To all whom it may concern;

Be it known thatwe, FRIEDRICH STOLZ, Ph. D., and Gnone' KoRNnoRFER," Ph. D., chemists, citizens of the Empire of Germany, 5 residing at Hochst -on-the-Main, Germany,

have invented new Pharmaceutical Products; and. we hereby declare the following to bea specification thereof. i The new pharmaceutical products are the IO esters of meta aminobenzoic acid, which are decomposed by heating with acids or alkalies intometa-aminobenzoic acid and an al kamin derivating from an aminoalcohol the arbon atoms of which'are linked in an open 1 5 hain. These alkamin esters of the meta- )aminobenzoic acid may be obtained by several methods. We prefer to synthetize them by reducing the corresponding metanitrobenzoic-acid alkaminester. The new aminobenzoic-acid alkamin esters are colorless compounds little soluble in water, 'but readily soluble in alcohol, ether, and benzene, of a low melting-point, and of alkaline reaction on litmus. Most-characteristic is their decomposition when heated with alkalies or acids, as they form then meta-aminobenzoic acid and an alkamin, deriving from an .aminoalcohol with an open carbon chain. With hydrochloric acid said esters form salts readily soluble in water to a neutral solution. The new esters have the property of producing local anaesthesia, and this roperty is in their neutral reacting hydroch orids not associated with any irritating effect.

The preparation of such an ester may occur, for instance, as follows: ten parts, b iweight, of meta nitrobenzoyldiethylarmnoethanol, which may be obtained by heating meta-nitrobenzoylchlorid with diethyl aminoethanol in resence of benzene, and which is an oil solub e with difliculty in water, are dissolved in twenty-five parts, by weight, of concentrated hydrochloric acid, to which are added twelve arts, by weight of tin, the reaction being a lowed to take place at a moderatetemperature. From the dilute solution the tin is then eliminated by means of hydrogen sulfid, and after filtration the metation of sodium carbonate may be precipitated and separated by shaking with ether. ,On evaporatingv the ethereal solution the new compound remains asan oil which solidifies aminobenzoyld'iethylaminoethanol on addiand may be recrystallized from li roin, then forming crystals having the me ting-point 45 to 47 centigrade; It is soluble in water with difiiculty, but readily soluble in ether, alcohol, and benzene. On heating with alkalies or acids the ester is decomposed, forming m'eta-aminobenzoic acid and diethylaminoethanol. With one equivalent of hydrochloric acid it forms ahydrochlorid readily soluble in water to a neutral reaction and crystallizingfrom alcoholin prisms, .melting at 118 to 120 centigrade.

In an analogous or different manner other alkamin esters v of meta-aminobenzoic acid. may be obtained showing the above-mentioned characteristics. J

Having now described our invention, what we claim is 1. As new products, those alkamin esters of meta aminobenz'oic acid which yield, when heated with acids or alkalies, metaaminobenzoic acid and an alkamin derivating from an aminoalcohol with an open chain of carbon atoms; the new esters being colorless com ounds, little soluble in water, readily solub le in alcohol, etherand benzene, of a kalin reaction on litmus, forming with hydrochloric acid salts soluble to. a neutral so- 'lution, which produce local anaesthesia without causing any irritation.

2; As a new product, the alkamin ester, meta-aminobenzoyldiethylaminoethanol, being a colorless com ound little soluble in water, readily solub e in alcohol, ether and benzene, solidifyingin the cold and melting at 45 to 47 centi rade, of alkaline reaction on litmus and w on heated with hydrometa-aminobenzoic acid and diethylaminoethanol, forminga salt with one equivalent of hydrochloric acid which crystallizes from alcohol in prisms melting at 118 to 120 centigrade," the'solution of which is of anesthetic action without causin irritation.

In testimony that we claim t e foregoing as our invention we have signed our names in presence of two subscribing witnesses.

FRIEDRICH sTo Lz. I GEORG KORNDORFER. Witnesses:

JEAN GRUND.

, CARL .GRUND.

chloric acid or soda-lye it is decomposed into 

